The proposed research will analyze the impact of changing social and economic conditions at the societal level and over the individual life course on the demographic behaviors of the population of a rural Italian community from 1865 to 1921. During this period the crude birth rate declined from 33 to 21, the crude death rate declined from 21 to 15, and rates of in- and out-migration were high. Coincident with these demographic changes, economic activity in the community shifted from non-wage to wage labor in both the rural industrial and agricultural sectors, and compulsory public education for children was introduced. These changes in social and economic conditions and demographic behaviors broadly resemble the modernization and demographic transition experienced by other European populations during the nineteenth and early twentieth centuries. While previous studies have been limited to the description of these vital processes for entire populations, the proposed research will identify and quantify differentials in the timing and level of mortality declines, birth limitation, and fertility decline for key population subgroups. This will permit us to evaluate alternative explanations of the fertility decline, including relationships to changes in mortality, migration, coresidence, work and industrialization. This study is possible because of the availability of a unique data base on 19,000 individuals assembled by the principal investigator over the past four years. This data base provides longitudinal information on births, marriages, deaths, immigrations, emigrations, coresidential arrangements, occupation, and income in readily accessible, machine-readable form. With a richness of longitudinal, individual-level data not available for the United States, Britain, or France, this study provides an unusual opportunity to analyze and explain the demographic transition. A variety of demographic and statistical methods, appropriate for the analysis of differentials in demographic behaviors, will be employed in the study.